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XML在地图制图与成果共享中的应用研究

测绘通报 2024年第S2期 293-296页

作者：李军利李富春中煤地西安地图制印有限公司

针对信息化时代下地图多元化应用场景中现有数据无法直接利用，不同地图制图平台中信息描述模型的不一致，导致不同平台之间数据难以共享的问题，本文剖析地图符号图形模型，研究XML的语法规则，设计XML表达图形符号的描述结构，实现了... 详细信息

针对信息化时代下地图多元化应用场景中现有数据无法直接利用，不同地图制图平台中信息描述模型的不一致，导致不同平台之间数据难以共享的问题，本文剖析地图符号图形模型，研究XML的语法规则，设计XML表达图形符号的描述结构，实现了XML对地图符号模型的描述。通过对地图数据的公开化、标准化表示，合理解决了上述问题。

关键词：成果利用地图符号模型 XML描述语法规则

A statistical learning based image denoising approach

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Frontiers of Computer Science 2015年第5期9卷 713-719页

作者： Ke TU Hongbo li fuchun SUN Department of Computer Science and Technology State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China

The image denoising is a very basic but important issue in the field of image procession. Most of the existing methods addressing this issue only show desirable performance when the image complies with their underlying assumptions. Especially, when there is more than one kind of noises, most of the existing methods may fail to dispose the corresponding image. To address this problem, we propose a two-step image denoising method motivated by the statistical learning theory. Under the proposed framework, the type and variance of noise are estimated with support vector machine （SVM） first, and then this information is employed in the proposed denoising algorithm to further improve its denoising performance. Finally, comparative study is constructed to demonstrate the advantages and effectiveness of the proposed method.

关键词： SVM image denosing multiple noises

基于lightGBM模型的甘肃省临夏县滑坡易发性评价

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水资源与水工程学报 2024年第1期35卷 197-205,216页

作者：何哲石玉玲李富春贾卓龙晏长根长安大学公路学院陕西西安710064 长安大学地质工程与测绘学院陕西西安710054 中国二十二冶集团有限公司西北分公司陕西西安710119

甘肃省临夏县地质环境复杂,滑坡灾害发育,对当地居民生产生活造成严重威胁,亦对工程建设的开展造成一定阻碍,因此,选取高效准确的机器学习方法对临夏县进行滑坡易发性评价具有重大意义。首先依据遥感影像和野外勘察资料,选取了1718处滑... 详细信息

甘肃省临夏县地质环境复杂,滑坡灾害发育,对当地居民生产生活造成严重威胁,亦对工程建设的开展造成一定阻碍,因此,选取高效准确的机器学习方法对临夏县进行滑坡易发性评价具有重大意义。首先依据遥感影像和野外勘察资料,选取了1718处滑坡样本,遴选了滑坡灾变的16种影响因子并建立滑坡影响因子评价体系;再结合预测精度和运行时间等指标对比了轻量级梯度提升机(lightGBM)模型与主流机器学习模型的性能;最后利用混淆矩阵分级方法进行了基于lightGBM模型的临夏县滑坡易发性评价。结果表明:临夏县重要滑坡影响因子为地表植被和地形地貌因子,其中土地覆盖为最主要影响因子;lightGBM模型预测精度高达0.931,且运行速度仅为11.7 s,既能保证高精度又极大提升了运行效率;在抽稀后的数据集上,lightGBM模型的预测表现、校准程度和分级结果均优于随机森林(RF)模型;混淆矩阵分级法的较高和高易发区内滑坡分布更为集中,在14.94%的区域内分布着86.86%的滑坡灾害点。滑坡易发性评价结果较好地反映了研究区内滑坡分布发育情况,可为当地工程建设及防灾减灾工作提供一定指导。

关键词：滑坡易发性评价轻量级梯度提升机机器学习甘肃省临夏县

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光热与光伏发电综合对比

电力工程技术 2024年第1期43卷 246-253页

作者：李富春刘飞邵成成田旭田炜一冯斌中国电力工程顾问集团西北电力设计院有限公司陕西西安710075 国网青海省电力公司经济技术研究院青海西宁810008 西安交通大学电气工程学院陕西西安710049

光伏发电和光热发电是太阳能发电的2种典型形式。光伏开发成本相对较低,但为保证系统安全稳定运行,须配置一定比例储能和分布式调相机,造成发电成本提升,而光热自带储热和出力友好性,因此目前对于光伏与光热的发展技术路线仍存在较大争... 详细信息

光伏发电和光热发电是太阳能发电的2种典型形式。光伏开发成本相对较低,但为保证系统安全稳定运行,须配置一定比例储能和分布式调相机,造成发电成本提升,而光热自带储热和出力友好性,因此目前对于光伏与光热的发展技术路线仍存在较大争议。文中以青海海西地区为例,基于同一时空太阳能辐照资源和出力特性,比较光伏+储能与光热的电力保障能力;然后从电网安全稳定支撑能力角度对光伏+储能+调相机与光热进行比较;最后基于光热和光伏成本下降趋势预测进行二者的经济性对比。研究结果表明,若将光热和光伏放到技术对等层面,则光热由于同时具备储热和常规发电机功能,能够为系统提供短路容量、无功补偿和转动惯量支撑,在成本下降后经济性与光伏+储能+调相机基本相当,甚至更优。

关键词：光伏光热储能分布式调相机电力保障日等效发电小时数旋转惯量容量费用

Mineralogy of the otoliths of naked carp Gymnocypris przewalskii (Kessler) from Lake Qinghai and its Sr/Ca potential implications for migratory pattern

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Science China Earth Sciences 2012年第6期55卷 983-990页

作者： ZHOU ling JIN ZhangDong li fuchun State Key Laboratory of＇Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 China Graduate University of Chinese Academy of Sciences Beijing 100049 China College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China

Otoliths are biogenic carbonate minerals whose microstructure and microchemistry have been used for age determination, stock identification, life history and environmental tracing. Using X-ray diffraction （XRD） and Fourier transform infrared （FTIR） spectroscopy, we have determined the mineral types and crystalline characteristics of three pairs of otoliths from naked carp Gymnocypris przewalskii, the predominant fish in Lake Qinghai. The results indicate that the mineral of both lapillus and sagitta of the naked carp is aragonite, and that of asteriscus is vaterite. The aragonite of lapillus has prefect crystallization. Given the shape of lapillus and the sensitivity of its aragonite to water chemistry, lapillus was used to analyze temporal Sr/Ca ratios along the maximal growth axis by an electron probe microanalyzer （EPMA）. Consistent variations of Sr/Ca ratios with a range of 1.0x10-3-5.0~10-3 on the long and short radii indicate that Sr/Ca ratios of lapillus potentially respond to the chemical compositions of the host waters during the period of the naked carp＇s growth and migration. Discontinuous （dark） zones of lapillus were formed during fall and winter when the naked carp grows slowly in Lake Qinghai, resulting in similar low Sr/Ca ratios to lake water, whereas incremental zones with higher St/Ca ratios respond to its migratory river waters during spring and summer. Various Sr/Ca ratios of incremental zones suggest that the migratory pattern of the naked carp may be much more flexible, rather than in a single river. Therefore, high-resolution otolith microchemistry of the naked carp can be used to trace its migratory behavior, which is of significance for determining its migratory pattern and life history of this precious species inhabiting the Tibetan Plateau.

关键词： Lake Qinghai naked carp otolith migration aragonite Sr/Ca ratio environmental tracer

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新型橡杜复合改性沥青的制备参数研究

新型建筑材料 2024年第2期51卷 138-143页

作者：仝宗良李富春李志刚中交四航局广州南沙工程有限公司广东广州510000 东南大学交通学院江苏南京211189

为改善橡胶沥青的高温性能和储存稳定性能,基于具有橡塑二重性的可再生资源——杜仲胶对橡胶沥青的改性增强机理,以沥青常规性能试验和微观观测为手段,研究了杜仲胶与橡胶粉反应时间和温度、橡杜复合改性剂掺量对橡杜复合改性沥青(REMA... 详细信息

为改善橡胶沥青的高温性能和储存稳定性能,基于具有橡塑二重性的可再生资源——杜仲胶对橡胶沥青的改性增强机理,以沥青常规性能试验和微观观测为手段,研究了杜仲胶与橡胶粉反应时间和温度、橡杜复合改性剂掺量对橡杜复合改性沥青(REMA)性能的影响,提出了最佳制备工艺。结果表明:杜仲胶能够显著改善橡胶沥青的性能,REMA具有很好的施工和易性和储存稳定性;改性剂掺量对REMA的性能有显著的影响,杜仲胶和橡胶粉反应时间对REMA影响较大,杜仲胶和橡胶粉反应温度对REMA影响较小。结合宏观性能试验结果和微观检测分析,制备REMA的最佳工艺参数为:杜仲胶和橡胶粉反应时间为1.0~1.5 h,杜仲胶和橡胶粉反应温度为170~180℃,橡杜复合改性剂掺量为基质沥青质量的20%~25%。

关键词：橡胶沥青杜仲胶复合改性制备工艺

Sm-Nd isotope study and dating on Honguleleng ophiolite in Xinjiang, China

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Chinese Science Bulletin 1999年第20期44卷 1914-1917页

作者： Zhangdong Jin Jianhua Huang fuchun li Nanjing Univ State Key Lab Res Mineral Deposits Nanjing 210093 Peoples R China

A study of the Sm-Nd isotope composition of Honguleleng ophiolite in Xinjiang, China, isochron age ((626±25)Ma),εNd(t) = 8.40,and its model age (TNdDM) in the range of 1 180-1 208 Ma, indicates that the ophiolite was formed in the late stage of the Upper Sinian. In combination with its facies association, petrochemistry, REE patterns, trace elements

关键词： ophiolite Sm-Nd isochron age Honguleleng Xinjiang.

Origin of li-F-rich granite: Evidence from high P-T experiments

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Science China Earth Sciences 2004年第7期47卷 639-650页

作者： li fuchun ZHU Jinchu RAO Bing JIN Zhangdong ZHANG linsong School of Resource and Environment Sciences Nanjing Agriculture UniversityNanjing 210095China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210093China Nanjing Institute of Geography and limnology Chinese Academy of SciencesNanjing 210008China

Though magmatic origin of li-F-rich granite has been supported effectively by the existence of volcanic and subvolcanic rocks and melt inclusions trapped in them with similar chemical compositions, evidence from high T-P experiments is poor up to now. To simulate the evolution process of li-F-rich granite and to interpret its forming mechanism, a series of melting-crystallization experiments were carried out. Under the conditions of 1×108 Pa and 570–700°C, a magmatic mineral association of quartz + alkali feldspar + lithium muscovite/ferromuscovite ± fluorite ± cassiterite is found in leucogranite-HF-H2O system. This indicates the following points: (i) Fluorite, light-colored muscovite and cassiterite can crystallize directly from the li-F-rich granitic melt. (ii) The coexistence of dark-colored micas (e.g. biotite) and light-colored micas (e.g. lithium muscovite and ferromuscovite) suggests that the muscovite granite and two-mica granite can be formed under magmatic condition. The zonal texture of micas is not the sole feature for the micas of hydrothermal origin. (iii) As crystallization proceeds, the SiO2 concentration of the residual melt decreases, while the Al2O3 and F concentrations and A/CNK, NKA/Si ratios of the melt incerese, favoring the formation of li-F-rich granites. Our experiment results are well consistent with the vertical zonation widely observed in rare metal bearing granites, and therefore provide strong experimental evidence for magmatic origin of li-F-rich granite.

关键词： fluorite lithium muscovite ferromuscovite cassiterite melt evolution li-F-rich granite high P-T experiment DOI: 10.1360/03yd0339

等新能源消纳能力视角下的青海电网光热发电效益评估

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青海电力 2024年第S01期43卷 1-7页

作者：傅旭黎建锋李富春张雨津党楠中国电力工程顾问集团西北电力设计院有限公司陕西西安710075

大力发展新能源发电是我国电力行业发展的重要目标,但仅靠风电、光伏来完成新能源消纳占比要求,将导致弃电率高居不下。光热发电储热环节具有调节能力,利用光热发电代替风电和光伏,可降低风电和光伏弃电率,同时发挥容量效益,降低火电装... 详细信息

大力发展新能源发电是我国电力行业发展的重要目标,但仅靠风电、光伏来完成新能源消纳占比要求,将导致弃电率高居不下。光热发电储热环节具有调节能力,利用光热发电代替风电和光伏,可降低风电和光伏弃电率,同时发挥容量效益,降低火电装机规模及煤耗。但光热发电的高成本限制了光热发电的发展,如何评估光热发电在电力系统中的效益,对光热发展具有重要意义。提出一种等新能源消纳能力约束下的光热电站效益评估方法,可综合考虑光热发电的新能源装机替代效益、降低火电装机的容量效益、减少火电发电量的煤耗效益,从而全面评估光热发电在系统中的效益。研究成果可为青海光热发电的效益评估提供参考。

关键词：光热电站新能源发电容量效益电量效益新能源弃电率